1. Field of the Invention
The present invention relates to construction equipment, e.g., a hydraulic shovel, and, in particular, to an excavator control apparatus.
2. Description of the Related Art
In general, shovel-type construction equipment includes a boom, an arm, and a bucket, which together comprise an operation section and are successively and rotatably connected to the body of the equipment. The boom, the arm and the bucket are each connected to cylinders that can be extended or retracted by operating a lever. Digging with such equipment must be carried out by a very experienced operator because each of the cylinders must be operated simultaneously. Because there are not enough experienced operators today, shovel-type construction equipment in which each of the cylinders is automatically controlled has been proposed. If such equipment is configured to perform an automatic digging routine so that the digging load remains constant, however, a significant variation in digging depth may occur due to changes in the hardness of the ground being dug or the presence of obstacles. As a result, precise digging is difficult to achieve. In particular, when the ground is excavated beyond the intended depth, refilling must take place and, therefore, digging efficiency is considerably reduced. In addition, in correcting the variations in digging depth, the automatic digging control mode must be canceled every time to operate the lever, which results in increased number of digging steps and reduces digging efficiency.